Many of the chemicals used in the semiconductor industry are fed into a reactor chamber by way of a carrier gas. In a common approach, the carrier gas “picks up” one or more chemicals when the carrier gas is passed through an ampoule reservoir containing the chemical(s). Depending on the method of delivery, the ampoule may be installed in a precursor distribution system (PDS) enclosure.
A network of manual and automated valves are typically required for the safe use, servicing and replacement of ampoules. The network of valves is used for various purposes, such as isolation, diversion, pump-purge and delivery. A traditional ampoule reservoir assembly includes a canister that is in fluid communication with an inlet port and an outlet port. A manual lock-out tag-out valve and a pneumatic valve are connected in series between the canister and the inlet port. Similarly, a manual lock-out tag-out valve and a pneumatic valve are connected in series between the canister and the outlet port. The lock-out tag-out valves provide a secure way to prevent fluid from escaping from the canister. The pneumatic valves provide for automated control of fluid communication of: 1) the carrier gas entering the inlet port, and 2) the combination of carrier gas and precursor exiting the outlet port.
However, traditional reservoir assemblies suffer from a number of functional drawbacks. For example, some of the chemicals used in semiconductor manufacturing must be maintained within well defined temperature and pressure ranges to minimize condensation and/or decomposition of the chemicals. The traditional reservoir configuration of having the manual and pneumatic valve connected in series results in a tortuous fluid pathway and an odd physical shape, both of which interfere with maintaining the chemicals within a required temperature range. Additionally, the traditional reservoir assembly takes up a considerable amount of space and has less than optimum servicing and/or replacement characteristics.
Therefore, a system that can maintain chemicals within well defined temperature and pressure ranges while taking up less space is needed.